Plug connecter



Jan. W3. G. B. BENANDER PLUG CONNECTER Filed May 19, 1954.

Invent 01 Geo ge B. BenQndeP His AUJOPTLGH.

Patented Jan. 14 1936' UNITED STATES PATENT OFFICE PLUG CONNECTER Application May 19, 1934, Serial No. 726,538

4 Claims.

This invention relates generally to electrical connecters and more particularly to separable plugs of the type used in connecting flexible conductors with portable electrical heating de- 5 vices, such as flat-irons, percolators, and the like.

These devices are provided with a socket to which the separable plug may be connected and from which it may be disconnected by exerting tension on the plug to overcome the engaging friction of the plug and socket.

It is an object of the present invention to form the plug itself so that it can be readily gripped to disconnect it manually from the 15 socket of an electrical device to which it is connected.

It is another object of the invention to prevent injury to the terminal connections of the flexible conductor associated with the plug when- 20 ever tension is placed on this conductor.

Other objects of the invention will be apparent upon reference to the following specification, describing a preferred embodiment of the invention, and to the appended claims.

25 In the drawing Fig. 1 is a view showing the assembled plug or switch, and Fig. 2 is a View, partly in section, showing the interior of the plug.

Referring now to the drawing, the plug con- 30 sists of a member I and a complementary member 2 which are molded from a suitable insulating material. One end of these members is fastened together by clamping plates 3, which are provided with a plurality of projections 4 35 adapted to fit into openings 5 on each of the members. The other end of these members is fastened together by a split ring 6 which fits over a semi-collar I in which each member terminates.

40 Each member I and 2 is provided with a bottom wall 8 and side walls 9 which define a main recess extending along the length of the members. A central ridge Ill extends along a por-' tion of the bottom wall 8 and divides the main 45 recess into two parallel subsidiary recesses H. In these subsidiary recesses are disposed spring terminal contacts I2 by means of which the plug is connected to the socket of a portable electrical heating device (not shown).

50 Each side wall 9 is provided with a reentrant portion l3 terminating in an arm It. The arms 14 extend outwardly beyond the remainder of the side walls and together with the reentrant portions l3 provide means for gripping the plug 55 to disconnect it from the socket of a portable device. To enable the plug to be more readily gripped, each reentrant portion i3 is provided with serrations l5.

A flexible conductor cord 16, comprising two insulated wires or conductors H, is introduced 5 into the interior of the plug through a flexible cord guard- 08, which is molded from a suitable insulating material such as rubber. The cord guard has at one end. a collar l9 which fits into a recess 20 in each member i and 2 and secures the cord guard to the plug when the members are fastened together.

In each of the members I and 2 the undivided main recess, which lies between the reentrant portion it of each side wall, is provided with 15 a stud 2|. Each wire ll! of the flexible cord it is given a half turn around one of the studs and is then connected to one of the spring terminal contacts l2 by means of a binding screw 22. When the plug is assembled, these studs are aligned and abut against each other thereby insuring that the wires H remain in a half turn about the studs. It is to be understood that instead of providing each member with a stud which is aligned with the stud on the other member when the plug is assembled, one of the members may be provided with a longer stud and the stud omitted from the other member. The half turn of the wires ll about the studs causes friction to be producedbetween the studs and the insulation on the wires when tension is placed on the flexible cord Hi. The friction thus produced relieves a large portion of any tension which may be placed on the flexible cord, for example, by the movement of 5 the portable device to which the plug is connected or by a pull on the cord, and consequently tends to prevent the wires I! from being pulled away from the binding screws 22 whenever tension is placed on the cord. As the wires l1 fit tightly in the restricted passage between the studs 2l and the reentrant portions l3 of the side walls, the friction between the insulation on these wires and the inner surface of the reentrant portions likewise tends to pre- 'vent any tension that may be placed on the flexible cord from injuring the terminal connections of the cord.

The present invention therefore provides a separable plug having side walls provided with reentrant portions terminating in outwardly extending arms which enable the plug to be readily gripped to disconnect it manually from a portable electrical device to which the plug is connected. The invention also provides a friction between the reentrant portion of the side walls and the insulation on the wires and the friction between the insulation on the wires. and the stud tend to relieve the tension and to prevent injury to the terminal connections of the cord.

It is to be understood that the invention is not to be limited to the particular form or arrangement of the parts shown and described herein, as it is evident that these may be changed and modified without departing from the scope of the present invention.

What I claim as new and desire to secure by Letters Patent of the United 'States, is:

1. As an article of manufacture, a plug comprising two complementary members of insulating material having bottom and side walls defining a recess provided with a pair of openings at one end for the insertion of terminals, terminal contacts disposed within said recess in alignment with said openings, said contacts having terminal receiving portions adjacent said openlugs and conductor receiving portions at the opposite ends thereof, reentrant portions in the side walls beginning at a point substantially opposite the conductor receiving ends of said contacts and terminating in outwardly extending arms which provide means for gripping the plug, and strain relieving means. between said reentrant portions for a conductor cord connected to said contacts.

2. As an article of manufacture, a plug comprising two complementary members of insulating material having bottom and side walls defining a main recess, a central ridge extending along part of the length of thebottom wall of at least one of said members and dividing said main recess into two subsidiary recesses each open at one end for the insertion of terminals, terminal contacts disposed within said subsidiary recesses, said contacts having terminal receiving portions adjacenLsaid openings and conductor receiving portions at the opposite ends thereof, reentrant portions in the side walls beginning at a point substantially opposite the conductor receiving ends of said contacts and terminating in outwardly extending arms which provide means for gripping the plug, and strain relieving means between said reentrant portions for 5 a conductor cord connected to said contacts.

3. As an article of manufacture, a plug comprising two complementary members of insulating material having bottom and side walls defining a main recess, a central ridge extending along part'of the length of the bottom wall of at least one of said members and dividing said main recess into two subsidiary recesses each open at one end for the insertion of terminals,

terminal contacts disposed within said subsidiary recesses, said contacts having terminal receiving portions adjacent said openings and conductor receiving portions at the opposite ends thereof, reentrant portions in the side walls beginning at a point substantially opposite the conductor receiving ends of said contacts and terminating in outwardly extending arms which provide means for gripping the plug, and a stud carried by at least one of said members and disposed in the undivided main recess between said reentrant portions and spaced from said central ridge, said stud providing a passage for a conductor between each side of said stud and said reentrant portions.

4. As an article of manufacture, a plug comat least one of said members and dividing said main recess into two subsidiary recesses each open at one end for the insertion of terminals,

terminal contacts disposed within said subsidiary recesses, said contacts having terminal receiving portions adjacent said openings and conductor 4 receiving'portions at .the opposite ends thereof, reentrant portions in the side walls beginning at a point substantially opposite the conductor receiving ends of said contacts and terminating in outwardly extending arms which provide 5 means for gripping the plug, a stud carried -by at least one of said members and disposed in the undivided main recess between said reentrant portions and spaced from said central'ridge and said reentrant portions, a conductor cord having a pair of conductors each of which is connected to one of said contacts, each of said conductors being crossed in a half turn about the stud and then extended through one of the passages between the stud andsaid reentrant portions.

GEORGE B. BENANDER. 

